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                              Exhibit (10)-6
                              Unicom Corporation and Commonwealth Edison Company
                              Form 10-K File Nos. 1-11375 and 1-1839

                              Unicom Corporation
                     1998 Long-Term Performance Unit Award
                    for Executive and Group Level Employees
                           Payable in 2001 under the
            Unicom Corporation Long-Term Incentive Plan, as amended


Unicom Corporation, an Illinois corporation (the "Company"), hereby grants to
each employee described in Section 1 hereof as of January 1, 1998 (the "Grant
Date"), in accordance with the provisions of the Unicom Corporation Long-Term
Incentive Plan, as amended (the "Plan"), a performance unit award (each, an
"Award") expressed as a number (the "Base Unit") of performance units, in the
amount and upon and subject to the restrictions, terms and conditions set forth
below. Capitalized terms not defined herein shall have the meanings specified in
the Plan.

1.   Eligibility.  Any employee of Unicom or its affiliates (collectively, the
     "Employers") who on the applicable Grant Date is one of the following: (i)
     an officer of Unicom or any affiliate (including, but not limited to,
     Commonwealth Edison Company), (ii) each Executive Level equivalent, and
     (iii) each Group Level equivalent shall be eligible for an award; provided,
     however, that individuals who become Group Level employees, Executives or
     Officers after the Grant Date and during the Performance Period (as
     hereinafter defined) (each, a "New Employee") shall also be eligible to
     receive an Award hereunder.

     The term "Employee" shall mean an Existing Employee, a New Employee or an
     Other Employee, as the case may be. For purposes of the above, the
     classification of an Employee shall be based upon classifications used by
     Unicom or Commonwealth Edison Company, or if a participant's employer
     maintains a system of pay classification different from that described
     above, upon a classification determined by such employer and Unicom to be
     comparable to the above described eligible classifications.

     Further, an employee who participates in another long term performance
     award program ("Other Award") sponsored by Unicom or one of its affiliates
     will not be eligible to participate in this Award. If such employee is no
     longer a participant in an Other Award, then he or she may be deemed
     eligible to participate in this Award and such Award shall be prorated in a
     method consistent with the one described for New Employees in Section 6.1.
     In addition, if a participant in this Award becomes a participant in an
     Other Award, then he or she will cease to participate in this Award and the
     Award shall be prorated in a method consistent with the one described for
     Permitted Terminations in Section 6.1.

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2.   Base Unit.  The Base Unit for each Award shall be a number (rounded to the
     nearest one hundredth) equal to (a) the product of (i) the Salary (as
     defined below) of the Employee receiving such Award multiplied by (ii) the
     applicable percentage set forth below, (b) divided by the closing price of
     a share of Common Stock as reported in The Wall Street Journal as New York
     Stock Exchange Composite Transactions for December 31, 1997:

<TABLE>
<CAPTION>
                                                           Applicable Percentage
                                                           ---------------------
<S>                                                        <C>
Chairman                                                            50%
President                                                           45%
Executive Vice President and CNO/President of Nuclear Generation    45%
Executive Vice President and President of Fossil Generation         40%
Senior Vice President                                               35%
Officer, other than as listed above                                 25%
Executive, other than as listed above                               20%
Group Level employee, other than as listed above                    15%
Other Employee           such percentage as shall be established by the
                         Committee for the particular Other Employee
</TABLE>

     For the purposes of calculating the Base Unit, "Salary" shall mean (i) with
     respect to an Existing Employee such Existing Employee's monthly scheduled
     rate of pay as of the first payday in 1998 multiplied by 12, together with
     the income from such Existing Employee's Deferred Compensation Units
     (whether such Units were granted by the Company or by ComEd), and (ii) with
     respect to a New Employee's Salary shall be such New Employee's monthly
     scheduled rate of pay as of the date such New Employee becomes a New
     Employee (the "Start Date") multiplied by 12, together with the income from
     such New Employee's Deferred Compensation Units (whether such Units were
     granted by the Company or by ComEd).

3.   Performance Period. The Performance Period shall commence on January 1,
     1998 and end on December 31, 2000.

4.   Payment Amount.  The amount payable in connection with an Award (a "Payment
     Amount") shall be a dollar amount determined with reference to the
     Employee's Base Value (as defined below) and the Company's percentile rank
     (from 1 to 100) (the "Company Rank"), in the Ranking (as hereinafter
     defined) for the Performance Period, calculated as follows:

          Below Minimum Level.  If the Company Rank is lower than the 25th
          percentile in the Ranking, then the Payment Amount shall be zero.

          Between Minimum Level and Standard Level.  If the Company Rank is at
          least the 25th percentile in the Ranking but not greater than the 49th
          percentile in the Ranking, then the Payment Amount shall equal the
          Base Unit multiplied by a fraction the numerator of which is the
          Company Rank multiplied by 2 and the denominator of which is 100.

          Between Standard Level and Maximum Level.  If the Company Rank is at
          least the 50th percentile in the Ranking but not greater than the 90th
          percentile in the

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          Ranking, then the Payment Amount shall equal the Base Unit multiplied
          by a fraction the numerator of which is the Company Rank multiplied by
          2.5 less 25 and the denominator of which is 100.

          Above Maximum Level.  If the Company Rank exceeds the 90th percentile
          in the Ranking, then the Payment Amount shall equal the Base Unit
          multiplied by 2.

     For purposes of the foregoing, the term "Ranking" shall mean a ranking
     determined based upon the Cumulative Total Shareholder Return (as
     hereinafter defined) for such Performance Period on the Company's Common
     Stock as compared to the Cumulative Total Shareholder Return for such
     Performance Period on the common stock of each corporation comprising the
     Dow Jones Utility Index (or any successor index); the term "Cumulative
     Total Shareholder Return" for a period shall mean the result obtained by
     dividing (i) the sum of (a) the cumulative amount of dividends on the
     common stock in question for such period, assuming reinvestment of said
     dividends in said common stock, and (b) the difference between the price
     per share of said common stock at the end and the beginning of such period,
     by (ii) the price per share of said common stock at the beginning of such
     period; and the term "Base Value" shall mean the result obtained by
     multiplying the Employee's Base Unit by the value of a share of Common
     Stock (as determined under Section 5 hereof).

5.   Settlement of Awards.  The Payment Amount shall become payable upon the
     last day of the Performance Period and shall be paid by the Company within
     90 days thereafter. The Payment Amount shall be paid 50% in cash and 50% in
     shares of Common Stock; provided, however, that, if the Employee elects
     under the Unicom Corporation Stock Bonus Deferral Plan to defer more than
     50% of the Payment Amount, the amount so deferred shall be paid in shares
     of Common Stock; and provided further, that shares that may become payable
     to an Employee hereunder shall not be issued if the aggregate number of
     shares payable to such Employee does not exceed 25 (and, in such case, cash
     shall be paid in an amount equal to the value of the shares that would have
     been issued but for this proviso). Fractional shares of Common Stock that
     may become payable to an Employee hereunder shall be issued if the shares
     issuable to such Employee exceed 25 and are held in non-certificated, book-
     entry or electronic form; otherwise, any such fractional shares shall be
     paid in cash. For the purposes of determining the number of shares of
     Common Stock payable pursuant to this Section, a share of Common Stock
     shall be valued at the average of the closing prices of a share of Common
     Stock as reported in The Wall Street Journal as New York Stock Exchange
     Composite Transactions during the calendar quarter ending on the last day
     of the Performance Period (appropriately adjusted for any stock-split,
     stock dividend or other similar event).

6.   Employment as an "Employee" for Less Than Full Performance Period.

     6.1.  Termination of Employment.  If an Employee's employment with the
     Company is terminated prior to the last day of the Performance Period for
     any reason other than as provided in the immediately following sentence,
     then no amount shall be payable hereunder. If an Employee's employment with
     the Company is terminated


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     prior to the last day of the Performance Period due to such Employee's (i)
     termination as a result of the sale or closing of a generating plant or
     ComEd's decision to have a third party provide the services provided by the
     functional group that includes such Employee (in any such case, a
     "Permitted Termination"), (ii) retirement under the pension plan of any of
     the Employers or (iii) death, then such Employee shall be entitled to an
     amount equal to the Payment Amount calculated in accordance with Section 4
     hereof multiplied by a fraction the numerator of which is the number of
     days in the Performance Period that have elapsed between the commencement
     of the Performance Period (in the case of an Existing Employee), or the
     Start Date (in the case of a New Employee), and the date of such Permitted
     Termination, retirement or death (as the case may be) and the denominator
     of which is the total number of days in the Performance Period. The Payment
     Amount for any New Employee whose employment is not terminated prior to the
     last day of the Performance Period shall be calculated in accordance with
     Section 4 hereof and shall be prorated by multiplying it by a fraction the
     numerator of which is the number of days in the Performance Period that
     have elapsed between such New Employee's Start Date and the last day of the
     Performance Period and the denominator of which is the number of days in
     the Performance Period. Any Payment Amount calculated in accordance with
     either of the two immediately preceding sentences shall be paid as provided
     in Section 5 hereof within 90 days after the last day of the Performance
     Period.

     6.2.  Promotions; Demotions.  If an Employee is promoted or demoted during
     the Performance Period to a level that is included within the definition of
     Employee, then such person shall be entitled to an Award equal to Payment
     Amount calculated in accordance with Section 4 hereof, but based upon the
     sum of the products of (i) the Base Unit applicable to each level held by
     such Employee during the Performance Period, multiplied by (ii) a fraction
     the numerator of which is the number of days during the Performance Period
     that such level was held and the denominator of which is the total number
     of days in the Performance Period. If an Employee is demoted during the
     Performance Period to a level below that included within the definition of
     Employee, then such person shall be entitled to an Award equal to the
     Payment Amount calculated in accordance with Section 4 hereof multiplied by
     a fraction the numerator of which is the number of days in the Performance
     Period that such person was at a level included within the definition of
     Employee and the denominator of which is the total number of days in the
     Performance Period.

     6.3.  Reduction of Payment Amount in Certain Circumstances.  In the event
     that an Employee takes a voluntary leave of absence or long-term disability
     during all or a portion of the Performance Period, the Payment Amount will
     be prorated by multiplying it by a fraction, the numerator of which is the
     number of days the Employee worked for an Employer (or Employers) during
     the Performance Period and the denominator of which is 1,096.

     6.4.  Employment.  As used in this Section 6, employment by the Company
     shall include employment by a corporation which is a "subsidiary
     corporation" of the Company, as such term is defined in Section (S)424 (and
     any successor section) of


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     the Internal Revenue Code of 1986, as amended, or any successor internal
     revenue law.

7.   Rights as a Stockholder.  No Employee shall have any rights as a
     stockholder of the Company with respect to any shares of Common Stock that
     may be payable hereunder unless and until such shares have been issued to
     such Employee or otherwise credited to an account for the benefit of such
     Employee.

8.   Additional Terms and Conditions of Award.

     8.1.  Nontransferability of Award.  In accordance with Section 13.5 of the
     Plan, no Award or other related benefit may, except as otherwise
     specifically provided by the Plan or by law, be transferable in any manner
     other than by will or the laws of descent and distribution, and any attempt
     to transfer any such Award or other benefit shall be void; provided,
     however, that the foregoing shall not restrict the ability of any Employee
     to transfer any cash or Common Stock received as part of the Payment
     Amount. In accordance with Section 13.5 of the Plan, Awards or other
     benefits payable under Awards shall not in any manner be subject to the
     debts, contracts, liabilities, engagements or torts of any person who shall
     be entitled to such Award or benefits, nor shall they be subject to
     attachment or legal process for or against such person.

     8.2.  Withholding Taxes.  As a condition precedent to the delivery to the
     Employee of cash or Common Stock hereunder and in accordance with Section
     13.4 of the Plan, the Company may deduct from any amount (including any
     Payment Amount) payable then or thereafter payable by the Company or any of
     its subsidiaries to the Employee, or may request the Employee to pay to the
     Company in cash, such amount as the Company or any of its subsidiaries may
     be required, under all applicable federal, state, local or other laws or
     regulations, to withhold and pay over with respect to the Award.

     8.3.  Compliance with Applicable Law.  Each Award is subject to the
     condition that if the listing, registration or qualification of the shares
     of Common Stock subject to the Award upon any securities exchange or under
     any law, or the consent or approval of any governmental body, or the taking
     of any other action is necessary or desirable as a condition of, or in
     connection with, the vesting or delivery of such shares hereunder, such
     shares may not be delivered, in whole or in part, unless such listing,
     registration, qualification, consent or approval shall have been effected
     or obtained.

     8.4.  Award Subject to the Plan.  This Award is subject to the provisions
     of the Plan, and shall be interpreted in accordance therewith.



2001 Plan Document
Approved at 12/10/97 CGCC meeting


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